Transceiver systems in wireless communication networks perform the control functions for directing signals among communicating subscribers, or terminals, as well as communication with external networks. Transceiver systems in wireless communications networks include radio base stations and distributed antenna systems (DAS). For the reverse link, or uplink, a terminal transmits the RF signal received by the transceiver system. For the forward link, or downlink, the transceiver system transmits the RF signal to a subscriber, or terminal, in the wireless network. A terminal may be fixed or mobile wireless user equipment unit (UE) and may be a wireless device, cellular phone, personal digital assistant (PDA), personal computer or other device equipped with a wireless modem.
The rapid increase in data (e.g., video) communication and content consumption has led to expansion of wireless communication networks. As a result, the introduction of next generation communication standards (e.g., 3GPP LTE-A, IEEE 802.16m) has led to improved techniques for data processing, such as carrier aggregation (e.g., 100 MHz) with 8×8 MIMO (Multiple-Input, Multiple-Output) and CoMP (Co-Operative Multi-Point). This in turn has created the need for radio access networks capable of handling wider bandwidths and an increasing number of antennas. These radio access networks will require a higher numbers of fiber links to connect the base stations to the remote radio units. In addition, it is desirable to provide carrier aggregation with Multiple-Input and Multiple-Output (MIMO) and Co-Operative Multipoint (CoMP) techniques to significantly increase spectral efficiency. The implementation of Co-Operative Multipoint techniques requires communication between the baseband units and requires an increasing number of optical or wireless links between the baseband units and the radio units to support the increased data rate achievable with these improved transmission schemes. The increasing number of links required for these techniques results in an undesirable increased infrastructure cost.
Compression techniques can be used to reduce the infrastructure cost by reducing the number of optical or wireless links required to transmit the data as well as by optimizing resources. However, utilizing the compression techniques currently known in the art, it is difficult to achieve an average compression ratio with reasonable signal degradation while also keeping the latency jitter low. Compression techniques known in the art are unable to adjust to the continually changing signal behavior and as such, suffer from very high latency jitter.
While there are compression techniques currently known in the art to improve the data transmission rate of the communication system, the existing compression techniques utilize predetermined compression parameters that do not address the changing signal behavior of the received signals. As such, it is difficult for the known compression techniques to achieve an average compression ratio with reasonable degradation when the signal behavior changes rapidly.
In addition, carrier aggregation employing 8×8 Multiple Input Multiple Output (MIMO) and Coordinated Multipoint (CoMP) transmission are important techniques under consideration in next generation communications standards, such as Third Generation Partnership Project (3GPP) Advanced Long Term Evolution (LTE-A) and IEEE 802.16m. The data rate of these next generation communication standards is significantly higher and would greatly benefit from an improved compression scheme.
Accordingly, there is a need for a method and apparatus for data compression in a communication system that employs carrier aggregation and that adapts to the continually changing behavior of the received data signal over time, thereby providing a compressed data signal having a reasonable level of latency jitter and an acceptable level of performance degradation.